Friday, July 17, 2009
Walter Cronkite RIP
So help me out here. We lose Walter Cronkite, but we still have Larry King? Really?
YouTube fun!
Check this out. It's not the first time I've seen this sort of thing, but they've done a relatively good job. It's not quite Cookie Masterson material, but I have high hopes that they'll get better over time.
Thursday, July 16, 2009
Amateur Radio license exam prep - The Arithmetic
The amateur radio technician exam is mostly about memorizing rules and facts. As such, the best advice I can give is to go visit the AA9PW practice exam generator page and take the test repeatedly until you stop regularly failing it. It's actually not that hard to guess most of the answers. The ones you can't guess, you can just learn by repetition as you keep taking the practice tests.
There is, however, some math you should learn how to do rather than memorize, as it is easier. The laws of physics that embody the math you need to learn are embodied by 3 basic formulae. They are, E=IR, P=IE, and C=λω
Now, I can see some of your eyes have just glazed over. But bear with me. It's not that hard. Honest.
The first formula is E=IR, which is known as Ohm's Law. It's the relationship between the voltage drop across a load of a given resistance with a given amount of current flowing through it.
E, perversely enough, is the mathematical symbol for voltage. No, it's not V, 'cause that one was taken (Volume). It's E. You'll just have to remember that one. Voltage is electrical potential, more or less. People often compare voltage and current to water running through hoses. Voltage is analogous to the water pressure.
I, again, perversely enough, is the mathematical symbol for current. Electrical current is measured in Amperes, or Amps for short. Current, using the same water analogy, is how much water moves through the hose in a given time.
R is electrical resistance. Resistance is measured in units called Ohms, denoted by the greek letter Ω.
The basic formula is listed as E=I×R, but if you divide both sides of the equation by R, you get I=E÷R. Divide both sides by I and you get R=E÷I. If you think of those divisions as fractions, then you wind up with this little graphic symbol you can use to remember the relationship:
So that circle represents the relationship. If you remove from the circle the unknown you want to solve for, what's left tells you what the rest of the equation will look like. For example, if you remove the I, you're left with E over R, or E÷R. If you remove the E, you're left with I next to R, or I×R.
So, take question T4D04, for example:
What is the resistance of a circuit when a current of 3 amperes flows through a resistor connected to 90 volts?
A. 3 ohms
B. 30 ohms
C. 93 ohms
D. 270 ohms
They want to know R, and they've supplied you with I and E. R=E÷I. In this case, R=90÷3, or 30. The answer is B.
The next formula relates voltage and current to power. Power is P, and is measured in Watts. I and E are current and Voltage, just like before. P=IE. And like before, the circle chart can be used to figure out all of the relationships:
Let's use question T4E06 as an example:
How many amperes are flowing in a circuit when the applied voltage is 120 volts DC and the load is 1200 watts?
A. 20 amperes
B. 10 amperes
C. 120 amperes
D. 5 amperes
They want to know the current (Amperes), and they've given you the power and voltage. I=P÷E. Or, in this case, I=1200÷120: 10. The correct answer is B.
The last one looks a little funnier, but in truth it's actually easier. The formula is C=λω - the speed of light is equal to the frequency of a wave times its wavelength. Well, the speed of light is 300,000,000 meters per second, or 300 million meters per second. Wavelengths are in meters, at least for the purpose of this exam, and frequency is measured in Hertz (abbreviated as Hz). One Hz is one cycle per second. If we divide both sides of the equation by a million, you wind up with the formula 300 = frequency in Mhz × wavelength in meters. We can make a circle chart up for that one too:
In this case, we will never have the 'top' of the chart be an unknown, so we wind up with only two formulas, both of which look the same: You divide 300 by either the frequency in MHz or the wavelength in meters, and you get the other value.
Take question T1C05:
Which amateur band are you using when transmitting on 146.52 MHz?
A. 2 meter band
B. 20 meter band
C. 14 meter band
D. 6 meter band
300÷146.52 is approximately 2. The correct answer is A.
This formula can also be used to figure out antenna lengths. Take question T9A11:
What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz?
A. 112 inches
B. 50 inches
C. 19 inches
D. 12 inches
146 MHz is 2 meters. A quarter wavelength is half a meter. Half a meter is about half a yard, or a foot and a half or about 18 inches. The correct answer is C.
And that's it. So far as I know, that's all the math you need to know and understand to pass the technician exam. All the rest of it is just rote memorization of facts and rules.
Good luck!
There is, however, some math you should learn how to do rather than memorize, as it is easier. The laws of physics that embody the math you need to learn are embodied by 3 basic formulae. They are, E=IR, P=IE, and C=λω
Now, I can see some of your eyes have just glazed over. But bear with me. It's not that hard. Honest.
The first formula is E=IR, which is known as Ohm's Law. It's the relationship between the voltage drop across a load of a given resistance with a given amount of current flowing through it.
E, perversely enough, is the mathematical symbol for voltage. No, it's not V, 'cause that one was taken (Volume). It's E. You'll just have to remember that one. Voltage is electrical potential, more or less. People often compare voltage and current to water running through hoses. Voltage is analogous to the water pressure.
I, again, perversely enough, is the mathematical symbol for current. Electrical current is measured in Amperes, or Amps for short. Current, using the same water analogy, is how much water moves through the hose in a given time.
R is electrical resistance. Resistance is measured in units called Ohms, denoted by the greek letter Ω.
The basic formula is listed as E=I×R, but if you divide both sides of the equation by R, you get I=E÷R. Divide both sides by I and you get R=E÷I. If you think of those divisions as fractions, then you wind up with this little graphic symbol you can use to remember the relationship:
So that circle represents the relationship. If you remove from the circle the unknown you want to solve for, what's left tells you what the rest of the equation will look like. For example, if you remove the I, you're left with E over R, or E÷R. If you remove the E, you're left with I next to R, or I×R.
So, take question T4D04, for example:
What is the resistance of a circuit when a current of 3 amperes flows through a resistor connected to 90 volts?
A. 3 ohms
B. 30 ohms
C. 93 ohms
D. 270 ohms
They want to know R, and they've supplied you with I and E. R=E÷I. In this case, R=90÷3, or 30. The answer is B.
The next formula relates voltage and current to power. Power is P, and is measured in Watts. I and E are current and Voltage, just like before. P=IE. And like before, the circle chart can be used to figure out all of the relationships:
Let's use question T4E06 as an example:
How many amperes are flowing in a circuit when the applied voltage is 120 volts DC and the load is 1200 watts?
A. 20 amperes
B. 10 amperes
C. 120 amperes
D. 5 amperes
They want to know the current (Amperes), and they've given you the power and voltage. I=P÷E. Or, in this case, I=1200÷120: 10. The correct answer is B.
The last one looks a little funnier, but in truth it's actually easier. The formula is C=λω - the speed of light is equal to the frequency of a wave times its wavelength. Well, the speed of light is 300,000,000 meters per second, or 300 million meters per second. Wavelengths are in meters, at least for the purpose of this exam, and frequency is measured in Hertz (abbreviated as Hz). One Hz is one cycle per second. If we divide both sides of the equation by a million, you wind up with the formula 300 = frequency in Mhz × wavelength in meters. We can make a circle chart up for that one too:
In this case, we will never have the 'top' of the chart be an unknown, so we wind up with only two formulas, both of which look the same: You divide 300 by either the frequency in MHz or the wavelength in meters, and you get the other value.
Take question T1C05:
Which amateur band are you using when transmitting on 146.52 MHz?
A. 2 meter band
B. 20 meter band
C. 14 meter band
D. 6 meter band
300÷146.52 is approximately 2. The correct answer is A.
This formula can also be used to figure out antenna lengths. Take question T9A11:
What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz?
A. 112 inches
B. 50 inches
C. 19 inches
D. 12 inches
146 MHz is 2 meters. A quarter wavelength is half a meter. Half a meter is about half a yard, or a foot and a half or about 18 inches. The correct answer is C.
And that's it. So far as I know, that's all the math you need to know and understand to pass the technician exam. All the rest of it is just rote memorization of facts and rules.
Good luck!
Where's the beef?
Apple released a new version of iTunes today. One of it's "features" is to disable syncing between iTunes and the Palm Pre. As usual, there were immediate cries of "foul" from the haters over this perceived anti-trust violation.
Back when iTunes music was locked up with DRM, I would probably have agreed. But all of the music in the iTunes Music Store is now unencrypted AAC. There's no real tie-in between the store and the iPod, at least when it comes to music (we can continue to argue over the DRM encrusted movies and TV shows). But Apple doesn't really have anything like a monopoly in video content - certainly nothing like the market leadership they have in the music arena.
Put a bit more overtly, there's nothing at all preventing anyone from buying any track they want from the store and importing it into their Pre. Even if the Pre doesn't play AAC audio files (which I can't imagine it wouldn't be able to do), iTunes can happily convert them to MP3.
It says something about the Pre folks that they would rather try and make their device work with iTunes than design their own music management interface. Heck, their device manager could just read the iTunes music directory structure and suck the music out of it if they wanted to. But writing sync software is hard, gosh darn it, and emulating an iPod to leverage the hard work your competitor has done for nearly a decade, well, that's a lot easier. Or, at least, it was.
Back when iTunes music was locked up with DRM, I would probably have agreed. But all of the music in the iTunes Music Store is now unencrypted AAC. There's no real tie-in between the store and the iPod, at least when it comes to music (we can continue to argue over the DRM encrusted movies and TV shows). But Apple doesn't really have anything like a monopoly in video content - certainly nothing like the market leadership they have in the music arena.
Put a bit more overtly, there's nothing at all preventing anyone from buying any track they want from the store and importing it into their Pre. Even if the Pre doesn't play AAC audio files (which I can't imagine it wouldn't be able to do), iTunes can happily convert them to MP3.
It says something about the Pre folks that they would rather try and make their device work with iTunes than design their own music management interface. Heck, their device manager could just read the iTunes music directory structure and suck the music out of it if they wanted to. But writing sync software is hard, gosh darn it, and emulating an iPod to leverage the hard work your competitor has done for nearly a decade, well, that's a lot easier. Or, at least, it was.
Sunday, July 12, 2009
There's a site for that
What amazes and sometimes amuses me about the Internet is the sheer variety. The secret ingredient on tonight's episode of Iron Chef America was Pineapple. I was intrigued by something Alton said made me curious, so I looked up the wikipedia article on pineapples, and since I had the computer in front of me, I wondered how one went about growing pineapples. Well, you ask a question, you you get an answer.
Back to D-ATV: 900 MHz amp
It's been a while, but I've decided to try and ready the ATSC transmitter for a possible placement as an additional output on K6BEN/R, at least to start with. I've talked with Ben (W2NYC) about it and he seems receptive.
I tested the DEMI 7730PAHS 70 watt 900 MHz amp. From what I can tell, I'm getting something like 35 watts out of the thing (the ATSC pilot is at about 33.7 dBm. If you measure the pilot, the signal's power level is about 11.8 dB up from that, so 45.5 dBm, which is about 35 watts), which actually is more than I expected, given the ~5 dB peak-to-average ratio of ATSC. That winds up, with the KP-20, being about 150 watts of ERP. That's still way low. By comparison, KFTL-CA transmits from the top of Mt. San Bruno with 15 kW of ERP. It barely cuts in and out here. My proposed signal is 20 dB down from that, and is double the frequency. That doesn't particularly bode well. The only TV station around here that will be doing ATSC with that little power is the proposed operation of KTVJ on Mt. Tamalpais on channel 4 at 300 watts of ERP. But channel 4 is 66-72 MHz - almost 4 octaves lower.
But really, there's nothing I can do but try. It will either work, or it won't.
I tested the DEMI 7730PAHS 70 watt 900 MHz amp. From what I can tell, I'm getting something like 35 watts out of the thing (the ATSC pilot is at about 33.7 dBm. If you measure the pilot, the signal's power level is about 11.8 dB up from that, so 45.5 dBm, which is about 35 watts), which actually is more than I expected, given the ~5 dB peak-to-average ratio of ATSC. That winds up, with the KP-20, being about 150 watts of ERP. That's still way low. By comparison, KFTL-CA transmits from the top of Mt. San Bruno with 15 kW of ERP. It barely cuts in and out here. My proposed signal is 20 dB down from that, and is double the frequency. That doesn't particularly bode well. The only TV station around here that will be doing ATSC with that little power is the proposed operation of KTVJ on Mt. Tamalpais on channel 4 at 300 watts of ERP. But channel 4 is 66-72 MHz - almost 4 octaves lower.
But really, there's nothing I can do but try. It will either work, or it won't.
Saturday, July 11, 2009
Military smoking ban
So I was walking by a newspaper and saw a headline suggesting that the military is considering a smoking ban.
Really?
"Alright, soldier! Here's your M-16, hand grenades and a parachute. You're going to Iraq to defuse IEDs. But we'd better not catch you smoking! That shit's dangerous!"
Really?
"Alright, soldier! Here's your M-16, hand grenades and a parachute. You're going to Iraq to defuse IEDs. But we'd better not catch you smoking! That shit's dangerous!"
Thursday, July 9, 2009
Iran meets Florida
Let's take a moment to compare and contrast.
Many Americans fully believe that George W. Bush actually lost the 2000 presidential election, or won it by foul means rather than fair. Similar accusations, though perhaps on a wider scale, have been leveled at Mahmoud Ahmadinejad relating to the recently completed presidential election in Iran.
Let's take a look back at 2000:
At every stage of the proceedings there were demonstrations on both sides both large and small. At no point was there widespread outages of cell phone or text messaging service, nor were there riot police making mass arrests, nor was Al Gore held in "protective custody" until it all blew over. Perhaps most pointedly, nobody actually died protesting the election outcome (so far as I know).
All that stands in rather stark contrast to the ongoing situation in Iran. It's patently obvious to any observer, and it must be just as plainly obvious to anyone on either side in Iran that the current government lacks a basic level of legitimacy that even Bush had achieved in January of 2001. It doesn't even matter at this point if Ahmadinejad's election tally is as correct as he claims. A government of, by and for the people should not need mass arrests, tear gas and riot police to keep it in power. That's as true for Iran as it once was for Vietnam.
The Washington Post once editorialized: "[South Vietnamese] President Thieu says he'll quit if he doesn't get more than 50% of the vote. In a democracy, that's not called quitting." They were (and are) absolutely right, but the fact Thieu actually said that out loud says far more about the legitimacy of his government. But Thieu at least had the fig leaf of trying to resist a guerilla campaign staged and funded by the neighboring state (North Vietnam). Iran's borders are secure (indeed, Iran has been accused of attempting to destabilize its neighbor Iraq in recent months). The only possible threat to Ahmadinejad is his own people. You can't say such a thing when describing a democratically elected government and still be making any sense.
Many Americans fully believe that George W. Bush actually lost the 2000 presidential election, or won it by foul means rather than fair. Similar accusations, though perhaps on a wider scale, have been leveled at Mahmoud Ahmadinejad relating to the recently completed presidential election in Iran.
Let's take a look back at 2000:
At every stage of the proceedings there were demonstrations on both sides both large and small. At no point was there widespread outages of cell phone or text messaging service, nor were there riot police making mass arrests, nor was Al Gore held in "protective custody" until it all blew over. Perhaps most pointedly, nobody actually died protesting the election outcome (so far as I know).
All that stands in rather stark contrast to the ongoing situation in Iran. It's patently obvious to any observer, and it must be just as plainly obvious to anyone on either side in Iran that the current government lacks a basic level of legitimacy that even Bush had achieved in January of 2001. It doesn't even matter at this point if Ahmadinejad's election tally is as correct as he claims. A government of, by and for the people should not need mass arrests, tear gas and riot police to keep it in power. That's as true for Iran as it once was for Vietnam.
The Washington Post once editorialized: "[South Vietnamese] President Thieu says he'll quit if he doesn't get more than 50% of the vote. In a democracy, that's not called quitting." They were (and are) absolutely right, but the fact Thieu actually said that out loud says far more about the legitimacy of his government. But Thieu at least had the fig leaf of trying to resist a guerilla campaign staged and funded by the neighboring state (North Vietnam). Iran's borders are secure (indeed, Iran has been accused of attempting to destabilize its neighbor Iraq in recent months). The only possible threat to Ahmadinejad is his own people. You can't say such a thing when describing a democratically elected government and still be making any sense.
Wednesday, July 8, 2009
The Spanish Jerry Springer
Since I'm an RF enthusiast, I scan around the various TV channels checking on reception. I even check on the foreign language ones more or less just because I'm interested. In doing so, I ran across an interesting find.
Scarlet and I occasionally tune into the Jerry Springer show. It's a bit of a guilty pleasure. What I discovered on KTNC was what I believe is the Spanish Jerry Springer. The show is called José Luis Sin Censura (Sin Censura translates to Uncensored). The set looks like a virtual clone of Jerry's set. I tried to look it up on Wikipedia and IMDB, and I couldn't tell if it was a blatant rip-off or if it was authorized. But it looks funny as hell.
Scarlet and I occasionally tune into the Jerry Springer show. It's a bit of a guilty pleasure. What I discovered on KTNC was what I believe is the Spanish Jerry Springer. The show is called José Luis Sin Censura (Sin Censura translates to Uncensored). The set looks like a virtual clone of Jerry's set. I tried to look it up on Wikipedia and IMDB, and I couldn't tell if it was a blatant rip-off or if it was authorized. But it looks funny as hell.
Sony makes good
I've lambasted Sony on numerous occasions. Well, to be fair, I'm not the only one. The last piece of Sony equipment I bought that didn't in some way disappoint me was a phone I bought back in 1993 or so. It's still out in the garage hooked up to the last POTS line in the house for emergencies. Well, Sony may have redeemed themselves. I'm still not 100% sure, though.
The product that did it is the HWS-BTA2W Bluetooth A2DP transmitter/receiver. I've put it out by the hot tub to use with the iPhone and XM streaming. The idea is that the XM app for the phone is not 100% perfect. It will sometimes have a hiccup that will keep it from working until you tap on it to retry. And if you play the music long enough, it will time out on inactivity. So because of that, it's sort of desirable to have the phone near the hot tub in a waterproof bag. Now that the phones support A2DP, bluetooth is the natural solution. I simply connected a 1/8" stereo to dual RCA audio cable between the line out port of the Bluetooth device and the two line-in ports of the amplifier for the speakers, and then paired it to my phone.
Alas, it's not total nirvana. For one thing, the hot tub is near the office. The office is where the Cell2tel is located. The Sony box is close by enough that the two will fight for the attention of my phone. So I have to tell the Cell2tel to "let go" of the phone by pushing the button on it before taking the phone outside. Once out there, I then need to turn the Sony box on. When I go back in, I need to reverse that procedure to get the Cell2tel working again. But that's not so bad. The other minor annoyance is that the WiFi signal doesn't quite reach the hot tub. The phone gets enough wifi signal to sign on, but actual data transfer doesn't work so well. So it's actually better to just turn off the WiFi and use 3G. But all those are just local considerations that affect my installation only. They're not condemnations of the device itself.
But there is one negative thing I can say about this product - it's overpriced. It's currently retailing for just shy of $80. I just bought a pair of LG A2DP headphones for just under $25 at Fry's. And those were battery operated and included headphones. This thing is a chip, two jacks, two buttons, a switch and two LEDs in a shiny plastic box with a wall wart and a short audio cable. It couldn't have cost them more than about $10 to build it. But It's a Sony! And they say that Apple gear is overhyped.
The product that did it is the HWS-BTA2W Bluetooth A2DP transmitter/receiver. I've put it out by the hot tub to use with the iPhone and XM streaming. The idea is that the XM app for the phone is not 100% perfect. It will sometimes have a hiccup that will keep it from working until you tap on it to retry. And if you play the music long enough, it will time out on inactivity. So because of that, it's sort of desirable to have the phone near the hot tub in a waterproof bag. Now that the phones support A2DP, bluetooth is the natural solution. I simply connected a 1/8" stereo to dual RCA audio cable between the line out port of the Bluetooth device and the two line-in ports of the amplifier for the speakers, and then paired it to my phone.
Alas, it's not total nirvana. For one thing, the hot tub is near the office. The office is where the Cell2tel is located. The Sony box is close by enough that the two will fight for the attention of my phone. So I have to tell the Cell2tel to "let go" of the phone by pushing the button on it before taking the phone outside. Once out there, I then need to turn the Sony box on. When I go back in, I need to reverse that procedure to get the Cell2tel working again. But that's not so bad. The other minor annoyance is that the WiFi signal doesn't quite reach the hot tub. The phone gets enough wifi signal to sign on, but actual data transfer doesn't work so well. So it's actually better to just turn off the WiFi and use 3G. But all those are just local considerations that affect my installation only. They're not condemnations of the device itself.
But there is one negative thing I can say about this product - it's overpriced. It's currently retailing for just shy of $80. I just bought a pair of LG A2DP headphones for just under $25 at Fry's. And those were battery operated and included headphones. This thing is a chip, two jacks, two buttons, a switch and two LEDs in a shiny plastic box with a wall wart and a short audio cable. It couldn't have cost them more than about $10 to build it. But It's a Sony! And they say that Apple gear is overhyped.
Tuesday, July 7, 2009
XM alarm clock
So I thought I'd share how I set up an XM alarm clock on the mac.
What you need to do, in the end, is somehow bring up their little plugin iframe content in a page. But in order to do that, you need to tickle the login page first. Fortunately, it's relatively easy to do with JQuery. What you do is make an AJAX call to the login page, and have the success function add an iframe to the page with the URL of the player.
You can download the html file here. You need to edit the HTML page to put in your credentials and the channel number that you want. If you save the resulting page somewhere on your machine and then double-click it in the finder, the resulting browser window should start playing the channel of your choice (assuming your machine has Internet connectivity).
To this point, this solution is platform independent, so long as your browser has the plugin support to play the audio stream. The next thing you need to do is somehow cause your machine to open the file at the time desired. I'm confident there's a way to do this on Windows, but I don't really care. So sorry.
On the mac, you use cron to schedule things. The thing you need to schedule is:
And that's all there is to it.
What you need to do, in the end, is somehow bring up their little plugin iframe content in a page. But in order to do that, you need to tickle the login page first. Fortunately, it's relatively easy to do with JQuery. What you do is make an AJAX call to the login page, and have the success function add an iframe to the page with the URL of the player.
You can download the html file here. You need to edit the HTML page to put in your credentials and the channel number that you want. If you save the resulting page somewhere on your machine and then double-click it in the finder, the resulting browser window should start playing the channel of your choice (assuming your machine has Internet connectivity).
To this point, this solution is platform independent, so long as your browser has the plugin support to play the audio stream. The next thing you need to do is somehow cause your machine to open the file at the time desired. I'm confident there's a way to do this on Windows, but I don't really care. So sorry.
On the mac, you use cron to schedule things. The thing you need to schedule is:
osascript -e 'open location "file:///path/to/html_file"'
And that's all there is to it.
Monday, July 6, 2009
The problem with DIY projects
This is why Heathkit failed.
If you've been following along, I built my own 30 watt per channel stereo audio amplifier, with a case. Twice, in fact.
While it did work out, you'd do well not to add up the cost:
The Velleman K4003 amp kit: $33.95.
24 VAC CT transformer: $13.95
Aluminum case: $21.00
Misc. parts: $10.00
Total: $78.90
Not including shipping and labor.
If you've been following along, I built my own 30 watt per channel stereo audio amplifier, with a case. Twice, in fact.
While it did work out, you'd do well not to add up the cost:
The Velleman K4003 amp kit: $33.95.
24 VAC CT transformer: $13.95
Aluminum case: $21.00
Misc. parts: $10.00
Total: $78.90
Not including shipping and labor.
Cruising the Vista
It's been a while since the introduction of Windows Vista, and I've successfully managed to avoid it.
Until now.
My Dad, on my advice, bought a Dell about 3 years ago. The idea was that if he had trouble with it, he'd have someone to call. Well, this weekend while I was home helping him figure out why his backups weren't working to par, his installation of XP Home just died utterly. Every time you attempt to start, no matter which way, you got the Stop 0x000007B, which translates, more or less, to "I can't find your boot disk." Never mind that starting the recovery console and running chkdsk worked just fine.
Ok, so just reinstall XP. Well, that failed because when it got to the point where it had booted the installation software from the hard disk (after it copied that stuff from the CD), it couldn't find it.
So I said to myself, "Why am I killing myself with this crap? Mom switched to a mac years ago and hasn't had any trouble like this." So we went through the list of things he does with his machine. And it boils down to all the stuff that comes free with OS X, Office, Quicken and (eventually, but not right now) TurboTax - all of which are available on the mac.
But it sucks to spring him with a bill for a $600 machine (actually, since his monitor is starting to show symptoms, I'd probably have steered him to an iMac, so it'd be $1200), plus an additional $175 worth of software on a holiday weekend, so the compromise was to first go to Fry's and buy the cheapest copy of Vista we could find - Home Basic Upgrade.
The installation went well enough, but one problem sprang up immediately. We were legitimately allowed to use the upgrade version, since this was a machine that was running XP Home before, but because XP Home was not bootable, we needed to perform a clean install of Vista - something the license key did not allow. That resulted in spending an hour on the phone with Microsoft for them to engage in the workaround that makes the installation think it was upgraded.
Now, let's set aside for a moment the fact that they've wasted an hour in the life of a paying customer. That's not the sort of thing that you talk about in the sales brochures of most successful products. Sure, some products require maintenance, but this entire waste of time was of Microsoft's own invention. It serves no purpose that advances my Dad's computer's ability to do what it needs to do. No, this is just the 2009 manifestation with Bill Gates' personal vendetta against the perceived evils of software piracy. Bah.
But let's look at this another way. What does it cost Microsoft to staff the call center that needs to handle all of these issues? How much of the cost of a copy of Vista goes towards paying for the licensing bullshit that does me, the paying customer, no good at all - in fact, wasted (so far) an hour of my time? Since the vast majority of Windows Vista installations are done by OEMs, would just dispensing with the licensing bullshit really cost Microsoft that much?
Next on the hit parade is UAC - User Access Controls. The "Cancel or allow?" dialogs that sprinkle out of virtually every administrative task in which you engage. Now, to be fair, when you perform certain system updates and administrative changes in OS X, it pops up an authentication dialog, which is more or less the same thing. But in OS X, there are far fewer of them, and they're really built around security related things that really should be gated.
To quote Irving Berlin, it's spinach, and I say the hell with it.
Until now.
My Dad, on my advice, bought a Dell about 3 years ago. The idea was that if he had trouble with it, he'd have someone to call. Well, this weekend while I was home helping him figure out why his backups weren't working to par, his installation of XP Home just died utterly. Every time you attempt to start, no matter which way, you got the Stop 0x000007B, which translates, more or less, to "I can't find your boot disk." Never mind that starting the recovery console and running chkdsk worked just fine.
Ok, so just reinstall XP. Well, that failed because when it got to the point where it had booted the installation software from the hard disk (after it copied that stuff from the CD), it couldn't find it.
So I said to myself, "Why am I killing myself with this crap? Mom switched to a mac years ago and hasn't had any trouble like this." So we went through the list of things he does with his machine. And it boils down to all the stuff that comes free with OS X, Office, Quicken and (eventually, but not right now) TurboTax - all of which are available on the mac.
But it sucks to spring him with a bill for a $600 machine (actually, since his monitor is starting to show symptoms, I'd probably have steered him to an iMac, so it'd be $1200), plus an additional $175 worth of software on a holiday weekend, so the compromise was to first go to Fry's and buy the cheapest copy of Vista we could find - Home Basic Upgrade.
The installation went well enough, but one problem sprang up immediately. We were legitimately allowed to use the upgrade version, since this was a machine that was running XP Home before, but because XP Home was not bootable, we needed to perform a clean install of Vista - something the license key did not allow. That resulted in spending an hour on the phone with Microsoft for them to engage in the workaround that makes the installation think it was upgraded.
Now, let's set aside for a moment the fact that they've wasted an hour in the life of a paying customer. That's not the sort of thing that you talk about in the sales brochures of most successful products. Sure, some products require maintenance, but this entire waste of time was of Microsoft's own invention. It serves no purpose that advances my Dad's computer's ability to do what it needs to do. No, this is just the 2009 manifestation with Bill Gates' personal vendetta against the perceived evils of software piracy. Bah.
But let's look at this another way. What does it cost Microsoft to staff the call center that needs to handle all of these issues? How much of the cost of a copy of Vista goes towards paying for the licensing bullshit that does me, the paying customer, no good at all - in fact, wasted (so far) an hour of my time? Since the vast majority of Windows Vista installations are done by OEMs, would just dispensing with the licensing bullshit really cost Microsoft that much?
Next on the hit parade is UAC - User Access Controls. The "Cancel or allow?" dialogs that sprinkle out of virtually every administrative task in which you engage. Now, to be fair, when you perform certain system updates and administrative changes in OS X, it pops up an authentication dialog, which is more or less the same thing. But in OS X, there are far fewer of them, and they're really built around security related things that really should be gated.
To quote Irving Berlin, it's spinach, and I say the hell with it.
Wednesday, July 1, 2009
Casing up the audio amp
The audio amp project turned out much better than I anticipated. There's just one hiccup to take care of before it's perfect.
First, a picture:
I had to cut a couple of square holes in the case to install a couple of the parts - namely the power switch and the power receptacle. So I just drilled a couple of holes in the middle of where the square holes needed to go and used a pair of files to enlarge them to the necessary size. It worked pretty well!
The right side is sort of the back panel and the left side is the front. The layout sort of winds up putting AC carrying wires rather close to the low voltage stuff, which is perhaps not the textbook way of doing it, but I don't intend to submit this thing for UL approval. The entire case is tied to ground, which ought to keep it safe enough once the cover is on and screwed in.
Note that each channel of the amp has the input grouped with the matching output. That way it's relatively easy to figure out left from right - in fact, there's no reason to label left and right, since the input is right next to the associated output. Of course, this might be a problem if your RCA cabling can't stretch far enough apart to hit both of them, but that's not a problem for my application.
You'll notice that leads from both sides of the AC in go over to the power switch. This is because the switch itself has a little neon light in it - it lights up when the unit is turned on. Bonus!
The one hiccup I mentioned above is that I put one of the big 2200 μF capacitors in backwards. When I applied power to the unit, it promptly started bubbling and smoking. The irony is that despite that, the amp works pretty well for brief periods. But I obviously can't leave it like that. I'm going to have to very carefully unbolt the heat sink, rotate the board up so I can get to the bottom, desolder and replace the blown cap and then put it back together - hopefully without wrecking the wiring job I did. Wish me luck!
First, a picture:
I had to cut a couple of square holes in the case to install a couple of the parts - namely the power switch and the power receptacle. So I just drilled a couple of holes in the middle of where the square holes needed to go and used a pair of files to enlarge them to the necessary size. It worked pretty well!
The right side is sort of the back panel and the left side is the front. The layout sort of winds up putting AC carrying wires rather close to the low voltage stuff, which is perhaps not the textbook way of doing it, but I don't intend to submit this thing for UL approval. The entire case is tied to ground, which ought to keep it safe enough once the cover is on and screwed in.
Note that each channel of the amp has the input grouped with the matching output. That way it's relatively easy to figure out left from right - in fact, there's no reason to label left and right, since the input is right next to the associated output. Of course, this might be a problem if your RCA cabling can't stretch far enough apart to hit both of them, but that's not a problem for my application.
You'll notice that leads from both sides of the AC in go over to the power switch. This is because the switch itself has a little neon light in it - it lights up when the unit is turned on. Bonus!
The one hiccup I mentioned above is that I put one of the big 2200 μF capacitors in backwards. When I applied power to the unit, it promptly started bubbling and smoking. The irony is that despite that, the amp works pretty well for brief periods. But I obviously can't leave it like that. I'm going to have to very carefully unbolt the heat sink, rotate the board up so I can get to the bottom, desolder and replace the blown cap and then put it back together - hopefully without wrecking the wiring job I did. Wish me luck!
Monday, June 29, 2009
Velleman K4003 2x30 watt audio amplifier
I blogged a couple days ago about the outdoor speakers I mounted on the patio. I'd like to talk a little bit more about the problem I had in setting this up and how I solved it.
It's hard to find a standalone stereo audio amplifier anymore.
You can find amplified speakers, typically intended for use with computers. Those do take line-in, but typically have integrated speakers which typically are designed for a desktop installation. It's not really the right thing for a patio, and the speakers you get are certainly not weather resistant.
You can find home stereo receiver/amplifiers, but those typically have AM/FM radios built-in at the very least, and typically even in this day and age still include phono preamps as well. If all you want to do is plug in something like an iPod, it's just overkill.
No, what I want is an audio amplifier that takes a single stereo line level input and has a pair of speaker connections. For controls, a simple volume knob and power switch is fine. No need for anything fancier.
Well, I've found a solution, though it does come in kit form, so you need to be good with a soldering iron. It's the Velleman K4003 2x30 watt audio amplifier.
I actually bought one of these a while ago for use out by the hot tub, where there's another pair of speakers set up. I used to have another amplifier kit that I had built before that ran on 12 vdc. The best I could do was a 12 volt wall-wart power supply, but that was inadequate for the purpose, since it introduced a nasty 60 Hz hum in the speakers. The Velleman amp, by contrast, is designed to run with a 12 vac bipolar power input. That is, you hook up a 24 VAC center tapped transformer.
With an iPhone hooked up to the patio speakers, the output is quite loud. But even so, it's not at all distorted. The levels are high enough that you'd want to use a volume control in front of the input. A dual gang 20 kΩ logarithmic pot works perfectly. You hook the "counterclockwise" end of each pot up to ground, the opposite end to the audio input, and hook the sweep of the pot up to the amp's audio input.
The kit is available from Jameco, part # 129138. A suitable transformer can also be had from them, part # 99654.
It's hard to find a standalone stereo audio amplifier anymore.
You can find amplified speakers, typically intended for use with computers. Those do take line-in, but typically have integrated speakers which typically are designed for a desktop installation. It's not really the right thing for a patio, and the speakers you get are certainly not weather resistant.
You can find home stereo receiver/amplifiers, but those typically have AM/FM radios built-in at the very least, and typically even in this day and age still include phono preamps as well. If all you want to do is plug in something like an iPod, it's just overkill.
No, what I want is an audio amplifier that takes a single stereo line level input and has a pair of speaker connections. For controls, a simple volume knob and power switch is fine. No need for anything fancier.
Well, I've found a solution, though it does come in kit form, so you need to be good with a soldering iron. It's the Velleman K4003 2x30 watt audio amplifier.
I actually bought one of these a while ago for use out by the hot tub, where there's another pair of speakers set up. I used to have another amplifier kit that I had built before that ran on 12 vdc. The best I could do was a 12 volt wall-wart power supply, but that was inadequate for the purpose, since it introduced a nasty 60 Hz hum in the speakers. The Velleman amp, by contrast, is designed to run with a 12 vac bipolar power input. That is, you hook up a 24 VAC center tapped transformer.
With an iPhone hooked up to the patio speakers, the output is quite loud. But even so, it's not at all distorted. The levels are high enough that you'd want to use a volume control in front of the input. A dual gang 20 kΩ logarithmic pot works perfectly. You hook the "counterclockwise" end of each pot up to ground, the opposite end to the audio input, and hook the sweep of the pot up to the amp's audio input.
The kit is available from Jameco, part # 129138. A suitable transformer can also be had from them, part # 99654.
DirecTV and KFTL
Let me start off this little rant by saying that I don't really watch KFTL. Most of their programming is either home shopping or the same religious whacko jabbering on and on about whatever. Not my cup of tea.
But they do run classic TV during the night (rather than infomercials), and once in a while when I've run past them with the analog tuner (before they transitioned last week), they were showing Victory At Sea, which has an amazing musical score, if nothing else.
Since they transitioned to digital, KFTL is somewhat difficult to pull in. The HDHomerun has them sort of in-and-out, depending on the weather conditions. The Samsung tuner brings them in a little better.
But the DirecTV receivers don't show KFTL in the channel list at all.
The DirecTV HR20/HR21/HR22 can tune local channels (the HR21 and HR22 need to have the AM21 ATSC tuner add-on), but they get the list of channels over the dish from DirecTV along with the program guide. You can't "scan" for channels with these receivers, you must pick and choose from the available channels they say you can have.
The good news is that you can pick two markets, in case some of the channels are from an adjacent market. This is how I am able to get the tuners to see KSBW and KCBA (you tell it 95050 for the San Francisco bay area DMA and 95060 for the Santa Cruz/Monterey/Salinas market). But if you get a channel that is not on their list... Well, then you *don't* get that channel.
KFTL is not on their channel list.
I've attempted to bring this up with DirecTV. The response I got from their customer service department was that KFTL was not on the list because it is an out-of-market station.
KFTL transmits from Mount San Bruno. There is no possibility that they could be any more in the San Francisco market than that unless they were on Sutro tower, which is one mile north and actually in the city of San Francisco.
In short, their assertion is factually incorrect.
I rather suspect that the issue is that since KFTL is a low power broadcaster that they're just to lazy to add it to the list.
Note that I'm not demanding that DirecTV carry KFTL over the dish as part of the local channels they provide for those who don't have an OTA antenna. But for those of us who can receive them, I think they should not stand in the way.
If you agree and are a DirecTV customer in the bay area, why not drop them a line? Tell them that if they want to lie about why they don't have KFTL in the lineup, they should try coming up with a lie that isn't demonstrably false.
But they do run classic TV during the night (rather than infomercials), and once in a while when I've run past them with the analog tuner (before they transitioned last week), they were showing Victory At Sea, which has an amazing musical score, if nothing else.
Since they transitioned to digital, KFTL is somewhat difficult to pull in. The HDHomerun has them sort of in-and-out, depending on the weather conditions. The Samsung tuner brings them in a little better.
But the DirecTV receivers don't show KFTL in the channel list at all.
The DirecTV HR20/HR21/HR22 can tune local channels (the HR21 and HR22 need to have the AM21 ATSC tuner add-on), but they get the list of channels over the dish from DirecTV along with the program guide. You can't "scan" for channels with these receivers, you must pick and choose from the available channels they say you can have.
The good news is that you can pick two markets, in case some of the channels are from an adjacent market. This is how I am able to get the tuners to see KSBW and KCBA (you tell it 95050 for the San Francisco bay area DMA and 95060 for the Santa Cruz/Monterey/Salinas market). But if you get a channel that is not on their list... Well, then you *don't* get that channel.
KFTL is not on their channel list.
I've attempted to bring this up with DirecTV. The response I got from their customer service department was that KFTL was not on the list because it is an out-of-market station.
KFTL transmits from Mount San Bruno. There is no possibility that they could be any more in the San Francisco market than that unless they were on Sutro tower, which is one mile north and actually in the city of San Francisco.
In short, their assertion is factually incorrect.
I rather suspect that the issue is that since KFTL is a low power broadcaster that they're just to lazy to add it to the list.
Note that I'm not demanding that DirecTV carry KFTL over the dish as part of the local channels they provide for those who don't have an OTA antenna. But for those of us who can receive them, I think they should not stand in the way.
If you agree and are a DirecTV customer in the bay area, why not drop them a line? Tell them that if they want to lie about why they don't have KFTL in the lineup, they should try coming up with a lie that isn't demonstrably false.
Thursday, June 25, 2009
Apple iPhone composite AV cable review
Now that XM streaming is available on the iPhone, I've really taken to it. We used to have a SkyFi2 that I was using as an alarm clock and for getting XM out by the hot tub and out on the patio. That SkyFi2 is now available on eBay. Instead, I'm going to use some very clever javascript to bring up the streams in Safari every morning as my alarm clock, and we'll take a phone out to the hot tub to stream it there.
For the patio, I decided to go all out. I wanted a way to both stream the music and charge the phone at the same time. I didn't really want to buy a dock, though, since both of our phones are in cases, and while the cases typically don't fit well in docks, they do tend to accept docking cables.
So I bought the Apple Composite AV cable. The idea is that the audio will plug into another one of those Jameco audio amplifier kits, and the speaker wires will go through the wall to outdoor speakers. The iPhone end of the AV cable will sit on a little shelf just inside the patio door.
The cable is a little bit expensive, but it does include a USB power port. One of Apple's "sugar cube" chargers and a dock cable are by themselves almost as expensive as this cable.
One note, though is that whenever this cable is connected, the internal speaker of the phone is disabled. All the UI sound effects go out the cable instead. Also, whenever the cable is connected, YouTube and the iPod video playback don't actually play on the iPhone's screen. Instead, they play out the video cable and you get a still image on the iPhone screen. Also, the phone's UI does not display on the TV.
The "genius" at the Apple store actually got that wrong. He said that the video would play on both screens.
But I'm actually reasonably satisfied with the result. I don't plan on playing video while it's connected this way, though I suppose I could use a projector and one of those outdoor inflatable screens to do an outdoor movie night...
For the patio, I decided to go all out. I wanted a way to both stream the music and charge the phone at the same time. I didn't really want to buy a dock, though, since both of our phones are in cases, and while the cases typically don't fit well in docks, they do tend to accept docking cables.
So I bought the Apple Composite AV cable. The idea is that the audio will plug into another one of those Jameco audio amplifier kits, and the speaker wires will go through the wall to outdoor speakers. The iPhone end of the AV cable will sit on a little shelf just inside the patio door.
The cable is a little bit expensive, but it does include a USB power port. One of Apple's "sugar cube" chargers and a dock cable are by themselves almost as expensive as this cable.
One note, though is that whenever this cable is connected, the internal speaker of the phone is disabled. All the UI sound effects go out the cable instead. Also, whenever the cable is connected, YouTube and the iPod video playback don't actually play on the iPhone's screen. Instead, they play out the video cable and you get a still image on the iPhone screen. Also, the phone's UI does not display on the TV.
The "genius" at the Apple store actually got that wrong. He said that the video would play on both screens.
But I'm actually reasonably satisfied with the result. I don't plan on playing video while it's connected this way, though I suppose I could use a projector and one of those outdoor inflatable screens to do an outdoor movie night...
The vanishing empire
I remember in my youth TV sets that had a UHF dial that went up to 83.
14-83 were UHF, adjacent 6 MHz channels, starting at 470 MHz. So ((83-14)+1)*6+470 = 890 MHz. And right above that was (and is) the 902-928 Mhz Amateur/ISM band.
So what happened?
Well, the first thing that happened was the creation of the cellular 800 MHz band. That brought the band down to channel 69 - moving the top end of the band down to 800 MHz.
Of course, just under two weeks ago, the band has been reduced down to channel 51 - and now the top end is at 700 MHz. That's 190 MHz that's been reallocated away - almost half of the UHF band.
But even that doesn't tell the whole story. Between channels 14 and 20 are a series of band sharing arrangements that make some of those channels unavailable in certain geographical areas around the country. Here in the San Francisco Bay Area, channels 15-18 are off-limits because 16 and 17 are used in San Francisco for land-mobile.
Low VHF may wind up being the next casualty. It is widely conceded that ATSC doesn't work terribly well on channels 2-6 because of the background noise levels. Can we really justify a nationwide set-aside of 54-72 MHz for the sake of 15 full power TV stations?
14-83 were UHF, adjacent 6 MHz channels, starting at 470 MHz. So ((83-14)+1)*6+470 = 890 MHz. And right above that was (and is) the 902-928 Mhz Amateur/ISM band.
So what happened?
Well, the first thing that happened was the creation of the cellular 800 MHz band. That brought the band down to channel 69 - moving the top end of the band down to 800 MHz.
Of course, just under two weeks ago, the band has been reduced down to channel 51 - and now the top end is at 700 MHz. That's 190 MHz that's been reallocated away - almost half of the UHF band.
But even that doesn't tell the whole story. Between channels 14 and 20 are a series of band sharing arrangements that make some of those channels unavailable in certain geographical areas around the country. Here in the San Francisco Bay Area, channels 15-18 are off-limits because 16 and 17 are used in San Francisco for land-mobile.
Low VHF may wind up being the next casualty. It is widely conceded that ATSC doesn't work terribly well on channels 2-6 because of the background noise levels. Can we really justify a nationwide set-aside of 54-72 MHz for the sake of 15 full power TV stations?
Michael Jackson, RIP
The only thing I really want to say about Michael Jackson is that I'll bet anyone who cares a dollar that within 10 years the same stupid rumors and stories about his death will circulate as they did about Elvis.
TV stations as 6 meter beacons, Take 2
So it turns out the list I posted yesterday may have been a pre-transition list, or it may just be wrong. Trip left a comment pointing to rabbitears.info, which looks like it has the best list available.
Thanks, Trip!
Thanks, Trip!
Wednesday, June 24, 2009
Hawking HBB1 Broadband Booster review
We have Vonage and an Apple AirPort Extreme. This isn't the happiest possible combination, since the AEBS lacks any sort of QoS capability. As a workaround, I used to have the FreeBSD machine hooked up as a bridge with dummynet giving priority to the packets from the Vonage box. But this is a pretty heavyweight solution and makes that machine part of the critical path for Internet connectivity in the house.
There just had to be a better way.
Turns out, there is.
The Hawking HBB1 is billed as a "broadband booster." There is almost no documentation available on the Internet about how it does what it does. My guess is that it simply gives priority over UDP packets over TCP, but that's just a guess. In any event, one thing I've discovered so far is that it helps to actually tell the box what your Internet connection's actual uplink bandwidth is. The idea is that for best results, you need to take the burden of dropping excess packets away from your modem (because the modem won't care which one it drops), and give that job to the HBB1. The HBB1 has the ability to test the available upload bandwidth, but I've had better results just telling it that our connection has 640 kbps (which is a tad less than the rated value of 768 kbps).
The HBB1 is just a Ubicom StreamEngine in a box. The StreamEngine has been built into many so-called "gaming" home routers. The HBB1 is a way to add this same thing to a router that doesn't have it - like the AEBS.
So you may be asking, why not just buy one of those routers instead of the AEBS. Well, the AEBS supports IPv6, which so far as I can tell no other home router available does.
Anyway, with this device in place, the Vonage box works just as well as it did when I had the FreeBSD QoS solution in place. They can be had for a very cheap price on eBay, so all in all, I'd say it's a worthwhile purchase.
There just had to be a better way.
Turns out, there is.
The Hawking HBB1 is billed as a "broadband booster." There is almost no documentation available on the Internet about how it does what it does. My guess is that it simply gives priority over UDP packets over TCP, but that's just a guess. In any event, one thing I've discovered so far is that it helps to actually tell the box what your Internet connection's actual uplink bandwidth is. The idea is that for best results, you need to take the burden of dropping excess packets away from your modem (because the modem won't care which one it drops), and give that job to the HBB1. The HBB1 has the ability to test the available upload bandwidth, but I've had better results just telling it that our connection has 640 kbps (which is a tad less than the rated value of 768 kbps).
The HBB1 is just a Ubicom StreamEngine in a box. The StreamEngine has been built into many so-called "gaming" home routers. The HBB1 is a way to add this same thing to a router that doesn't have it - like the AEBS.
So you may be asking, why not just buy one of those routers instead of the AEBS. Well, the AEBS supports IPv6, which so far as I can tell no other home router available does.
Anyway, with this device in place, the Vonage box works just as well as it did when I had the FreeBSD QoS solution in place. They can be had for a very cheap price on eBay, so all in all, I'd say it's a worthwhile purchase.
Bye bye, text messaging
Push notification has arrived on the iPhone, and in particular the AIM client. And I've used it for a day now, and it works perfectly, so far as I can tell. It's so good that it will make a perfect replacement for text messaging. On the iPhone, AIM is free, but text messages aren't.
Now, it's not perfect - everyone you talk to needs to have a mobile AIM client, or else they'll have to keep using text messages, and the coming ability to send multimedia messages wouldn't integrate with AIM the same way it would with text messaging. But for the most part, this ought to dramatically lessen our need for text messaging from now on.
Perhaps this will result in AT&T dropping the ridiculously draconian pricing scheme for text messaging. The value of it has certainly been dramatically reduced.
Now, it's not perfect - everyone you talk to needs to have a mobile AIM client, or else they'll have to keep using text messages, and the coming ability to send multimedia messages wouldn't integrate with AIM the same way it would with text messaging. But for the most part, this ought to dramatically lessen our need for text messaging from now on.
Perhaps this will result in AT&T dropping the ridiculously draconian pricing scheme for text messaging. The value of it has certainly been dramatically reduced.
TV stations as 6 meter beacons
It used to be that if you lived in a place where there was no TV channel 2 broadcaster, you could tune your 6 meter receiver to 55.25 MHz to see if the 6 meter band was open. If it was, you'd find the video carrier of a TV broadcaster on channel 2.
With the change to digital, one would think that that trick would be a thing of the past, but that's not necessarily true. ATSC also includes a pilot frequency too - typically about 300 kHz up from the bottom end of the channel - 54.3 kHz or so for channel 2.
Also, there are fewer low-VHF broadcasters with the switch to digital than there used to be. Low VHF is not the best choice for ATSC because of the higher level of background electrical noise, so most broadcasters who formerly used low VHF have moved their digital transmitters to UHF instead.
There are a few high power stations on low VHF, though. Here's a list:
With the change to digital, one would think that that trick would be a thing of the past, but that's not necessarily true. ATSC also includes a pilot frequency too - typically about 300 kHz up from the bottom end of the channel - 54.3 kHz or so for channel 2.
Also, there are fewer low-VHF broadcasters with the switch to digital than there used to be. Low VHF is not the best choice for ATSC because of the higher level of background electrical noise, so most broadcasters who formerly used low VHF have moved their digital transmitters to UHF instead.
There are a few high power stations on low VHF, though. Here's a list:
| City | Channel | Call |
|---|---|---|
| Butte, MT | 2 | KTVM |
| Chicago, IL | 3 | WBBM |
| Cleveland, OH | 2 | WKYC |
| Grand Junction, CO | 2 | KREX |
| Grand Rapids, MI | 2 | WOOD |
| Harrisburg, PA | 4 | WHP |
| Las Vegas, NV | 2 | KVVU |
| Lexington, KY | 4 | WDKY |
| Macon, GA | 4 | WMAZ |
| Rapid City, SD | 2 | KOTA |
| Roanoke, VA | 3 | WBRA |
| Tallahassee, FL | 2 | WTWC |
Saturday, June 20, 2009
The link between DirecTV and Kindle
The Kindle is an interesting device in a relatively uninteresting market (to me, anyway. I understand that lots of folks appreciate books more than I do). What's interesting about it to ne isn't really the screen or anything like that, it's whispernet. Whispernet is the wireless data connection built into each Kindle. When you buy an eBook for the Kindle, it just magically appears a few minutes later. This happens because a cellular data modem is built-in.
Well, DirecTV receivers need to occasionally upload a relatively small amount of data to their headquarters once or twice a month or so, and sometimes would like to know it's geographical location to within a zip code.
Guess what: cell data modems can do just that.
DirecTV receivers could replace their built-in phone line modem with a GSM modem and antenna. The SIM card could be built in to the receiver's crypto card. Folks would no longer need to plug a phone cord into their receivers.
The one rub is that DirecTV needs to offer service in places where there is no cellular service or the signal is unusable. The workaround for that would be to have a USB modem that could connect the receiver to a landline the way they do today.
The other idea for people who live in a cellular service area, but don't have service near the receiver, would be to put the GSM modem physically on the dish, and let the receivers talk to it the same way they talk to the SWM. USB modems for laptops can be made only an inch or two long. A GSM modem could be made in a similarly sized plastic block with a pair of F connectors on either end and tap into the cable for power and data I/O.
The big question is whether or not there's anyone at DirecTV who can make the logical leap that would be required to see how this would make sense for them.
Well, DirecTV receivers need to occasionally upload a relatively small amount of data to their headquarters once or twice a month or so, and sometimes would like to know it's geographical location to within a zip code.
Guess what: cell data modems can do just that.
DirecTV receivers could replace their built-in phone line modem with a GSM modem and antenna. The SIM card could be built in to the receiver's crypto card. Folks would no longer need to plug a phone cord into their receivers.
The one rub is that DirecTV needs to offer service in places where there is no cellular service or the signal is unusable. The workaround for that would be to have a USB modem that could connect the receiver to a landline the way they do today.
The other idea for people who live in a cellular service area, but don't have service near the receiver, would be to put the GSM modem physically on the dish, and let the receivers talk to it the same way they talk to the SWM. USB modems for laptops can be made only an inch or two long. A GSM modem could be made in a similarly sized plastic block with a pair of F connectors on either end and tap into the cable for power and data I/O.
The big question is whether or not there's anyone at DirecTV who can make the logical leap that would be required to see how this would make sense for them.
6to4 for iPhone?
It occurs to me that adding IPv6 support to the iPhone, or indeed any mobile device like it, would be relatively easy. Since they have a routable IPv4 address, they could easily do 6to4. When on via WiFi, they could use router and prefix solicitation when available, and when not, then it simply wouldn't be available, but there's really no reason why 6to4 couldn't be used on the WAN interface. It isn't as if it adds any overhead when it isn't being used. The benefit would be the ability to surf IPv6 only sites transparently, plus moves us all closer to IPv6 adoption. It also would pave the way for AT&T to upgrade the network to native IPv6 with IPv4 support via NATPT. That too could be accomplished transparently, if they were careful.
Friday, June 19, 2009
XM on iPhone
I listened to XM through my iPhone pretty much all day long while I worked today. I even did it over A2DP headphones. The experience was almost completely seamless.
One glitch is that while the iPod app pops up an audio device selector widget when there's an A2DP headphone available, 3rd party apps do not. This means that initially you may need to use the iPod to play a snippet of some audio, then select the A2DP headphones, then flip over to the XM app and fire it up. Once you start it, however, it sticks with your A2DP device for as long as it can.
XM sounds to me as good as it ever does in the car when the phone has WiFi. It's slightly worse over 3G, but it's certainly acceptable. It worked well while I was on CalTrain - no pauses or gaps.
The only part of the experience that leaves anything to be desired it's the cost. XM is $12.95/mo if you don't have a radio at all - equivalent to the cost of their full radio package, even though they leave out some channels (mostly news and talk) that they don't have internet streaming rights for. If you have a radio on the $13/mo plan, be prepared to shell out an additional $3/mo for streaming privileges.
It seems to me we've seen this dance before: a company struggling financially raises prices in order to try and drive up revenue. Inevitably the result of such short-sighted thinking is a rush for the exits. Sigh.
But it's worth it to me at least for as long as they can make it last.
One glitch is that while the iPod app pops up an audio device selector widget when there's an A2DP headphone available, 3rd party apps do not. This means that initially you may need to use the iPod to play a snippet of some audio, then select the A2DP headphones, then flip over to the XM app and fire it up. Once you start it, however, it sticks with your A2DP device for as long as it can.
XM sounds to me as good as it ever does in the car when the phone has WiFi. It's slightly worse over 3G, but it's certainly acceptable. It worked well while I was on CalTrain - no pauses or gaps.
The only part of the experience that leaves anything to be desired it's the cost. XM is $12.95/mo if you don't have a radio at all - equivalent to the cost of their full radio package, even though they leave out some channels (mostly news and talk) that they don't have internet streaming rights for. If you have a radio on the $13/mo plan, be prepared to shell out an additional $3/mo for streaming privileges.
It seems to me we've seen this dance before: a company struggling financially raises prices in order to try and drive up revenue. Inevitably the result of such short-sighted thinking is a rush for the exits. Sigh.
But it's worth it to me at least for as long as they can make it last.
iPhone 3GS
Well, that was painless, for the most part. I went to stand in line at the Valley Fair Apple store at 5:30 AM and I had an iPhone 3GS in my hands by 6:15 AM this morning. I didn't actually leave the building with it until 6:45, though, thanks to AT&T. Recall that I had swapped the SIM card with Scarlet's phone so she could enjoy the 3G this week. I had to momentarily undo that for the purpose of the 3GS acquisition, however, because officially my phone number wasn't due for a free upgrade yet. So officially Scarlet's number got the 3GS upgrade, and then we swapped SIM cards back again. Cumbersome, but in the end it was successful.
The compass reminds me a little bit of a compass you might use on the deck of a ship - it's a little bit unstable and while it usually points generally in the right direction, it jumps around a little. It also has this tendency to require you to "recalibrate it" by moving the phone in a figure 8 motion. Whenever I hold the phone out and do this, Scarlet giggles a little. She says it reminds her of something you'd see a snake charming swami do.
When I got to work, I paired the phone with my A2DP capable bluetooth headset. That seems to have been a totally painless exercise. I can now listen to Sirius/XM with the phone while not having to leave the browser on the computer pointing to the XM streaming server. The audio quality of the XM streams is quite nice, even when you get it over 3G. The downside is that, since it's a 3rd party app, it can't stream the audio in the background under other apps, like the built-in iPod app can. Maybe this is something Apple can loosen up with further API modifications later.
The only downside there is that I have to switch back and forth between the iPhone and the hockey-puck audio transmitter connected to the audio out on my work machine. I might wind up just choosing to use the wired headphones for the phone and the BT set for the computer like it was before.
The other downside now is that I have an inactive iPhone 2G now to get rid of. I suspect eBay will be saturated with them, and now that the 3G is being sold for $99, their value has plummeted. I also have a small collection of iPhone 2G cases that we no longer have any use for.
The compass reminds me a little bit of a compass you might use on the deck of a ship - it's a little bit unstable and while it usually points generally in the right direction, it jumps around a little. It also has this tendency to require you to "recalibrate it" by moving the phone in a figure 8 motion. Whenever I hold the phone out and do this, Scarlet giggles a little. She says it reminds her of something you'd see a snake charming swami do.
When I got to work, I paired the phone with my A2DP capable bluetooth headset. That seems to have been a totally painless exercise. I can now listen to Sirius/XM with the phone while not having to leave the browser on the computer pointing to the XM streaming server. The audio quality of the XM streams is quite nice, even when you get it over 3G. The downside is that, since it's a 3rd party app, it can't stream the audio in the background under other apps, like the built-in iPod app can. Maybe this is something Apple can loosen up with further API modifications later.
The only downside there is that I have to switch back and forth between the iPhone and the hockey-puck audio transmitter connected to the audio out on my work machine. I might wind up just choosing to use the wired headphones for the phone and the BT set for the computer like it was before.
The other downside now is that I have an inactive iPhone 2G now to get rid of. I suspect eBay will be saturated with them, and now that the 3G is being sold for $99, their value has plummeted. I also have a small collection of iPhone 2G cases that we no longer have any use for.
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